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JavaScript Number() Function

Function Reference JavaScript Functions

Definition and Usage

The Number() function converts the object argument to a number that represents the object's value.

If the value cannot be converted to a legal number, NaN is returned.

Syntax

Number(object)

Parameter Description
object Optional. A JavaScript object. If no argument is provided, it returns 0.

Tips and Notes

Note: If the parameter is a Date object, the Number() function returns the number of milliseconds since midnight January 1, 1970 UTC.

Example

Example

Convert different object values to their numbers:

<script type="text/javascript">

var test1= new Boolean(true);
var test2= new Boolean(false);
var test3= new Date();
var test4= new String("999");
var test5= new String("999 888");

document.write(Number(test1)+ "<br />");
document.write(Number(test2)+ "<br />");
document.write(Number(test3)+ "<br />");
document.write(Number(test4)+ "<br />");
document.write(Number(test5)+ "<br />");

</script>

The output of the code above will be:


Try it yourself »

Function Reference JavaScript Functions

From http://www.w3schools.com (Copyright Refsnes Data)